1. Field of the Invention
One embodiment of the disclosed invention relates to a lighting device using organic electroluminescence (EL).
2. Description of the Related Art
An organic EL element has been actively researched and developed. In the fundamental structure of the organic EL element, a layer containing a light-emitting organic compound is interposed between a pair of electrodes. By applying voltage to this element, light emission from the light-emitting organic compound can be obtained.
The organic EL element can be formed into a film; thus, a large-area element can be easily formed. Therefore, the organic EL element has a high utility value as a surface light source that can be applied to lighting or the like.
For example, a lighting device including an organic EL element is disclosed in Patent Document 1.